Human Immunodeficiency Virus (HIV) (cont.)

Mary D. Nettleman, MD, MS, MACP

Mary D. Nettleman, MD, MS, MACP is the Chair of the Department of Medicine at Michigan State University. She is a graduate of Vanderbilt Medical School, and completed her residency in Internal Medicine and a fellowship in Infectious Diseases at Indiana University.

Charles Patrick Davis, MD, PhD

Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.

What is the history of HIV?

Although HIV infection is only a recent
discovery, scientists have shown that HIV-1 may have spread to humans over 100
years ago. The likely source was primate-to-human transmission through bites or
blood exposure, with chimpanzees being the most likely candidate for HIV-1
transmission to humans.

Isolated human cases existed long before HIV infection came to the attention
of the physicians. It is not entirely clear what caused HIV to begin to spread
more widely in the mid-20th century. HIV was identified in tissue preserved
from patients who died as early as 1959. In the late 1960s or early 1970s, it is
thought that HIV infection spread to Haiti and then to the United States.
Entering the homosexual male community predominately, the virus began to spread
among people with multiple sexual partners. Over time, often a decade after
infection, people with HIV infection began to get unusual infections, develop
AIDS, and die.

In 1981, the Centers for Disease Control and Prevention first took note of a
cluster of pneumonia causes by Pneumocystis jirovecii (formerly known as
Pneumocystis carinii), which was a highly unusual pathogen to find in young men.
Affected individuals were noted to have depleted counts of a specific type of
immune cell, known as the CD-4 T cell. Subsequent investigation revealed that
homosexual men with multiple partners were most likely to have disease,
suggesting that sexual activity was a key factor in transmission. Soon,
scientists discovered the
disease in people injecting illicit drugs, in heterosexuals with
multiple sexual partners, in people who received blood products, and in babies
born to infected mothers. A global effort was undertaken to identify the virus,
leading to the description of HIV as the likely cause of AIDS by Dr. Luc Montagnier in
France and by Dr. Robert Gallo in the United States. A test for HIV was soon developed and
used to diagnose individuals and to ensure the safety of the blood supply.